Apparatus for coating recessed surface areas



Nov. 20, 1962 w. c. BORNEMANN APPARATUS FOR COATING RECESSED SURFACEAREAS Filed Feb. 15, 1961 Ff'a. 1

1 1 G 5 INVENTOR. zVi ZZz'czm CB United States Patent Ofifice iifihdfizdPatented Nov. 20, 1952 3,064,620 APPARATUS FGR CQATING RECESSED URFAEAREAS C. Bornemann, 1538 S. Highway 83,

Villa Park, 111. Filed Feb. 13, 1%1, Ser. No. 88,853 12 Claims. (Cl.118-3) The present invention pertains to coating apparatus. Moreparticularly it has to do with the apparatus for coating recessedsurface areas such as indicia cast in a preferably transparent plate.The method disclosed herein embodying the invention is covered in mycopending application Serial No. 189,944, filed March 26, 1962.

Indicia bearing displays such as signs, instrument panels and theintelli nce media may be formed by casting or incising the indicia intoa surface in reverse or mirror image. The recessed areas are then coatedwith a material, such as paint, to provide the necessary contrast to setout the configuration of the indicia so that they may be readilyobserved from the opposite side of the plate. One use of presentationsof this sort for an example is for dial plates in radios and the like.Often, the indicia is cut into a sheet of transparent material such asLucite. Upon illumination of the plate into which the indicia are outeither by edge or back lighting, the painted recessed portions stand outvividly.

One prior method of applying a coating to the recessed areas is to sprayor otherwise cover the entire surface of the plate with material andthen to wipe oil" the excess, leaving the coating only within therecesses. Such a technique is most wasteful of time and of the coatingmaterial. Another approach has been to carefully paint the coatingmaterial into the recesses with a brush. This is exceedingly costly intime, especially when done by hand.

it is accordingly a general object of the present invention to providean apparatus for coating recessed areas of the kind described and yetwhich avoid the aforenoted disadvantages.

Another object of the present invention is to provide an apparatus forcoating areas recessed into a plate automaticall and with a minimum oftime and ellort.

Still another object of the present invention is to provide an apparatusof the foregoing character which is rugged capable oi rapidly coatingthe recesses with a minimum of waste, either as to efiort or material.

An apparatus constructed in accordance with the present inventionincludes a table upon which the recessed plate is disposed forcontrolled vibration. Overlying the table is a housing, and a pl -alityof tubes that communicate with an project dowrvardly therefrom with thetubes being disposed in a configuration corresponding to that of therecessed areas in the plate. A reservoir of coating material is includedwithin the housing. Freely slidable within each tube is a needle havingits lower end projecting below the tube and its upper end closinglyengageable with the upper end of the tube. The apparatus furtherincludes means for lowering the housing to press the needle lower endsagainst the recessed areas and displace the needle upper ends fromengagement with the tubes, permitting the coating material to flowevenly and gently into the recessed areas.

The features of the invention which are believed to be new are set forthwith particularity in the appended claims. The invention, together withfurther obiects and advantages thereof, may best be understood however,by reference to the following description taken in conjunction with theaccompanyirlt drawings. in which:

FIG. 1 is a perspective view, partia ly in crosssection, showingapparatus embodying the present invention;

FIG. 2 is a fragmentary cross-sectional view taken along the lines 22 inHS. 1;

PEG. 3 is a fragmenentary perspective view of a portion of a platebearing indicia-representing recessed areas;

PEG. 4 is a fragmentary cross-sectional end view of the apparatus shownin FIG. 1; and

FIG. 5 is a schematic diagram depicting the wave shape of a vibrationimparted to the apparatus shown in FIGS. 1, 2 and 4.

The present invention pertains to apparatus for coating, with a materialsuch as paint, recessed area 10 formed in a surface of a plate ll (FIG.3). For example, as to one area of utility, by filling recesses area 1%with an opaque paint and forming plate ll from a translucent ortransparent material such as Lucite, back lighting of the latter causesthe coated recessed area to stand out with a high degree of visibility.Dial plates of radio apparatus commonly incorporate indicia means ofthis kind.

As illustrated for purposes of explaining the present invention, theapparatus includes a table 12. upon which the plate ll is disposed forcoating of its recessed areas. Overlying table 12 is an enclosure 13'.Enclosure i3 is supported upon posts 3.4 projecting upwardly from table12 and enabling movement or the enclosure toward and away from thetable. Downward movement of enclosure 33' is limited by an upwardlyprojecting stop 12 threaded through table 12.

Secured within the lower portions of enclosure 13 is a first dispenserhousing 13-. Projecting downwardly from housing 13 and communicatingwith the interior thereof are a plurality of tubes 15 arranged in aconfiguration corresponding to recessed areas 10 and in plate ll. For agiven application, at least one such tube 15 preferably is disposed inalignment with each linear portion of the indicia character formed inplate 11.

Freely slidable within tubes 15 are respective needles 16, the lowerends 17 of which project beyond the lower ends of tube 15. Preferably,the lower end portion of the tubes are bent inwardly toward but spacedfrom needles 16. The upper end of each of needles 16 is flared to form avalve member loo closingly engageable with the correspondingly flaredinner side walls of tubes 15.

The interior of housing 13, about needles 16, constitutes a reservoir 18for the coating medium, in this instance an opaque or semi-opaque painthaving a consistency preferably between that of a paste and that ofwater. Upon lowering of en losure 13' and hence of housing l3 towardplate 12, the lower end of needles l6 engage the bottom of recessedareas 10 whereupon the needles are moved upwardly relative to tube 15.In consequence, the coating material is permitted to flow down wardlyfrom reservoir ll through the tube and gently into recessed area lit.Upon subsequent raising of housing 13, the upper end of needle 16 closeswith that of tube 15 and thereby inhibits further disposition of thecoating material.

More precise control of needles and of the disposition of the coatingmaterial is insured by including elements within housing 13 to maintaineven and proper distribution of the coating material into all of thetubes. To this end, immediately overlying the upper ends of needles 1%is a layer 19 of elastomer material impervious to the coating medium butperforated at 19a for the downward flow of paint. A thin layer ofperforated elastomer is suitable to rest upon the valve member 16a tocause closmovement thereof. Immediately above material layer 19 is alayer 29 of resilient matter such as felt which is likewise pervious toand is absorbtive of the coating medium. Adding evenness of coatingmaterial distribution is attained by th edisposition over layer 2% of aplurality of small lead shot 21, or other suitable weights to help inthe operation of the valve member 16a.

In order to permit the disposition of a plurality of different coloredcoating mediums respectively to different ones of the recessed areas,the apparatus preferably includes a tandem arrangement of dispensingapparatus. To this end, a second housing 25 is disposed above housing 13and is similarly constructed insofar as it includes a reservoir for thecoating medium together with layers 19' and 28' corresponding to layers19 and 28 and weights 21 corresponding to weights 2-1, all as previouslydescribed, Tubes enclosed needles 16, project downwardly from housing 25through housing 13. Tubes 15 are otherwise similar to tubes 15 and arearranged in a desired configuration with respect to a portion of therecessed areas It in plate 11.

Introduction of the coating materials into housings 13 and 25 isaccommodated by access openings 27 and 23, respectively. One color ofcoating medium may be inserted into one reservoir and a differentcolored coating medium inserted into the other.

Movement of housings 13 and 25 downwardly toward plate 12 positions thelower ends of tubes 15 and 15' immedidiately above recessed areas 19. Atthe same time, the lower ends of needles 16 and 16' engage the recessedareas whereupon the needles are forced upwardly to disengage their upperends from those of tubes 15 and 15'. Thereupon, a passage is openedbeneath layers 19 and 19" permitting the coating mediums to flowdownwardly through tubes 15 and 15 and into recessed areas 10. Uponsubsequent raising of housings 13 and 25, needles 16 and 16 are urgeddownwardly and into sealing engagement at the upper ends of tubes 15 and15', terminating the flow of coating medium through the tubes.

Increased assurance of opening and closing the needle valve members 16aand against undesired splattering of plate 11 is enjoyed by placinghousings 13 and 25 alternately under pressure and vacuum. To this end,the reservoir areas of each housing communicates with a pressure controlunit 30 coupled through a conduit 31 to a source of compressed air andthrough a conduit 32 to a vacuum pump. In a conventional manner, controlunit 30 is synchronized, through a micro-switch system (not shown), toadmit pressure with the coating medium reservoirs upon downwardpositioning of housings 13 and 25. Similarly, upon the subsequentraising of housings 13 and 25, the reservoirs are placed incommunication with conduit 32; the resultant vacuum within thereservoirs tends to draw the coating medium upwardly within tubes 15 and15 thereby positively inhibiting further discharge.

In order to obtain both uniform and complete coating of the entiresurface area of recessed areas 10, the plate 11 and bed 12 preferablyare subjected to vibration. To this end, transducer units 33 and 34 aresecured respecti"ely on the bed 12 near the side and the end wallrespectively, although the bed 12 is made of light material such asaluminum, it is preferred that the transducers be supported on the bedand operate directly in the plate 11. Upon lowering of housings 13 and25 to a position at which needles 16 and 16 engage recessed areas ittransducers 33 and 34 are energized through microswitches on theirundersides to vibrate plate 11 in two horizontal directions. Vibrationis terminated upon withdrawal of tubes 16 and 16 from'their loweredposition, the vibration preferably being maintained for a short durationfollowing removal of theneedles from contact with the recessed areas.Most advantageous coatng is obtainable byvibrating the plate 11 with aclipped sinewave motion as represented in FIG. 5. More particularly,such motion is clipped on one-half cycle of the housing movement asindicated by the wave form shown in FIG. 5. Abrupt clipping of thehousing movement is readily attainable by placing a stop in the' path ofthe movement of the transduced element or within the transducers 33 and34. Thus, the paint which contacts the plate 11 in the grooves It),acquires momentum with the plate during the sine-wave portion of themotion and this momentum causes the paint to flow and spread in thegrooves to points remote from the needle when the sinewave motion of theplate is clipped as where the plate is abruptly stopped. The vibrationsotherwise are rapid and of short excursion, the frequency being variablyadjusted for optimum results during operation in view of dirTerentweights of plates which will be processed.

it is also to be noted that this vibration efiective upon the needlescontacting the plate and shakes the needle to assist in the paint flowtherethrough, which, alongwith the vertical movement of the needle inthe ports, keeps the flow path open for the paint to fiow when free todo so. This vibration can be done by hand also but there should be forbest results a repeated sudden stopping of the plate after movement ofthe paint with the plate has been instituted. However, the transducersmay need only strike the plate sharply after being stationarymomentarily and similar results will be performed provided the plate isreturned to the starting position by a spring or by a second blow madesharply after the plate has come to rest following the first blow.

As herein modified, a multiplicity of colors of "coating material may bedispensed, It will be readily understood that still further dispensingunits may be disposed in tandurn with the two described in order toincrease the number of colors aflixed in a single operation.

The apparatus described above is capable of dispensing a coatingmaterial such as paint into indicia representing recesses while sodispensing only the exact amount of paint required and thereby avoidingwastage. 'In addi-' tion, the dispensed coating medium is cause to floweven ly over the entire recessed area yet the apparatus is longenduring. Durability and ease of handling are also best obtained byfabricating the housing structure of a lightweight material such asaluminum. I

Thus needles of common size and flow characteristics may be employedwith recesses of any width, the vibra tion of the plate in the directionof the greatest width of the indicia recesses being adjusted Whether infrequency While a particular embodiment of the present inven' tion hasbeen shown and described, it will be obvious to those skilled in the artthat changes and modifications may be made without departing from theinvention in its broader aspects. Accordingly, the aim in the appendedclaims is to cover all such changes and modifications as fall within thetrue spirit andscope of the invention.

What is claimed is:

1. Apparatus for coating areas recessed into a plate comprising: a tableupon which said plate is disposed; a housing overlying said table; aplurality of tubes com municating with and projecting downwardly fromsaid housing with said tubes disposed in a configuration cor respondingto that of said recessed areas; a reservoir of coating medium withinsaid housing; a needle freely s1id' able within each of said tubes witheach needle having its lower end projecting below the tube and its upperend closingly engageable with the upper end of the tube; and means forlowering said housing to press said needle lower ends against saidrecessed areas and displace said needle upper ends from engagement withsaid tubes.

2. Apparatus for coating areas recessed into a plate comprising: a tableupon which said plate is disposed; a housing overlying said table; aplurality of tubes communicating with and projecting downwardly fromsaid housing with said tubes disposed in a configuration correspondingto that of said recessed areas; a reservoir of coating medium withinsaid housing; a needle freely slidable within each of said tubes witheach needle having its lower end projecting below the tube and its upperend closingly engageable with the upper end of the tube, the lower endportion of each tube being bent inwardly toward but spaced from theneedle; and means for lowering said housing to press said needle lowerends against said recessed areas and displace said needle upper endsfrom engagement with said tubes.

3. Apparatus for coating areas recessed into a plate comprising: a tableupon which said plate is disposed; a housing overlying said table; aplurality of tubes communicating with and projecting downwardly fromsaid housing with said tubes disposed in a configuration correspondingto that of said recessed areas; a reservoir of coating medium withinsaid housing; a needle freely slidable within each of said tubes witheach needle having its lower end projecting below the tube and its upperend closingly engageable with the upper end of the tube; means forlowering said housing to press said needle lower ends against saidrecessed areas and displace said needle upper ends from engagement withsaid tubes; and means for vibrating said housing during engagement ofsaid needles with said recessed areas.

4. Apparatus for coating areas recessed into a plate comprising: a tableupon which said plate is disposed; a housing overlying said table; aplurality of tubes communicating with and projecting downwardly fromsaid housing with said tubes disposed in a configuration correspondingto that of said recessed areas; a reservoir of coating medium withinsaid housing; a needle freely slidable within each of said tubes witheach needle having its lower end projecting below the tube and its upperend closingly enga eable with the upper end of the tube; means forlowering said housing to press said needle lower ends against saidrecessed areas and displace said needle upper ends from engagement withsaid tubes; and means for vibrating said housing during and afterengagement of said needles with said recessed areas.

5. Apparatus for coating areas recessed into a plate comprising: a tableupon which said plate is dispose a housin overlying said table; aplurality of tubes communicating with and projecting downwardly fromsaid housing with said tubes disposed in a configuration correspondingto that of said recessed areas; a reservoir of coating medium withinsaid housing; a needle freely slidable within each of said tubes witheach needle having its lower end projecting below the tube and its upperend closingly engageabl with the upper end of the tube; means forlowering said housing to press said needle lower ends against saidrecessed areas and displace said needle upper ends from engagement withsaid tubes; and means for vibrating said housing with a clippedsine-wave motion during engagement of said needles with said rccessedareas.

6. Apparatus for coating areas recessed into a plate comprising: a tableupon which said plate is disposed; a housing overlying said table; aplurality of tubes commun cating with and projecting downwardly fromsaid housing with said tubes disposed in a configuration correspondingto that of said recessed areas; a reservoir of coating medium withinsaid housing; a needle freely slidable within each of said tubes witheach needle having its lower end projecting below the tube and its upperend closingly engageable with the upper end of the tube; means forlowering said housing to press said needle lower ends against saidrecessed areas and displace said needle upper ends from engagement withsaid tubes; and means for vibrating said housing with a sine-wave motionclipped on one-half cycle during engagement of said needles with saidrecessed areas.

7. Apparatus for coating areas recessed into a plate comprising: a tableupon which said plate is disposed; a housing overlying said table; aplurality of tubes communicating with and projecting downwardly fromsaid housing with said tubes disposed in a configuration correspondingto that of said recessed areas; a reservoir of coating medium withinsaid housing; a needle freely slidable within each of said tubes witheach needle having its lower end projecting below the tube and its upperend tclosingly engageable with the upper end of the tube; means forlowering said housing to press said needle lower ends against saidrecessed areas and displace said needle upper ends from engagement withsaid tubes; and means for creating pressure within said housing duringengagement of said needles with said recessed areas.

8. Apparatus for coating areas recessed into a plate comprising: a tableupon which said plate is disposed; a housing overlying said table; aplurality of tubes communicating with and projecting downwardly fromsaid housing with said tubes disposed in a configuration correspondingto that of said recessed areas; a reservoir of coating medium withinsaid housing; a needle freely slidable within each of said tubes witheach needle having its lower end projecting below the tube and its upperend closingly engageable with the upper end of the tube; means forlowering said housing to press said needle lower ends against saidrecessed areas and displace said needle upper ends from engagement withsaid tubes; and means for creating a vacuum within said housing uponwith drawal of said needles from said recessed areas.

9. Apparatus for coating areas recessed into a plate comprising: a tableupon which said plate is disposed; a housing overlying said table; aplurality of tubes communicating with and projecting downwardly fromsaid housing with said tubes disposed in a configuration correspondingto that of said recessed areas; a reservoir of coating medium withinsaid housing; a needle freely slidable within each of said tubes witheach needle having its lower end projecting below the tube and its upperend closingly engageable with the upper end of the tube; means forlowering said housing to press said needle lower ends against saidrecessed areas and displace said needle lower ends from engagement withsaid tubes; and means for creating pressure within said housing duringengagement of said needles with said recessed areas and for creating avacuum Within said housing upon withdrawal of said needles from saidrecessed areas.

10. Apparatus for coating areas recessed into a plate comprising: atable upon which said plate is disposed; a first housing overlying saidtable; a first plurality of tubes communicating with and projectingdownwardly from said housing with said tubes disposed in a configurationcorresponding to that of a first portion of said recessed areas; areservoir of coating material within said first housing; a needle freelyslidable within each of said first plurality of tubes with each needlehavingits lower end projecting below the tube and its upper endclosingly engageable with the upper end of the tube; a second housingoverlying the first housing; a second plurality of tubes communicatingwith and projecting downwardly from said second housing through saidfirst housing with said second plurality of tubes disposed in aconfiguration correspondmg to that of another portion of said recessedareas; a reservoir of a second coating medium within said secondhousing; a needle freely slidable within each of said second pluralityof tubes with each needle having its lower end projecting below the tubeand its upper end closingly engageable with the upper end of the tube;and means for lowering said housings to press said needle lower endsagainst said recessed areas and displace said needle upper ends fromengagement with said tubes.

11. Apparatus for coating areas recessed into a plate comprising: atable upon which said plate is disposed; a hous ng overlying said table;a plurality of tubes com muntcating with and projecting downwardly fromsaid houslng with said tubes disposed in a configurat on correspondingto that of said recessed areas; a needle freely slidable within each ofsaid tubes with each needle having its lower end projecting below thetube and its upper end closingly engageable with the upper end of thetube; means for lowering said housing to press said needle lower endsagainst said recessed areas and displace said needle upper ends fromengagement with said tubes; a layer of material pervious to a coatingmedium and disposed in said housing to overlie said needle upper ends; alayer of re- 7 silient matter pervious to said medium and overlying saidmaterial; a layer of elements exerting pressure on the upper surface ofsaid resilient matter; and a reservoir of said coating medium withinsaid housing and above said layer of resilient matter.

12. Apparatus for coating areas recessed into a plate comprising: atable upon which said plate is disposed; a housing overlying said table;a plurality of tubes communicating with andprojecting downwardly fromsaid housing with said tubes disposed in a configuration correspondingto that of said recessed areas; a needle freely slidable Within each ofsaid tubes with each needle having its lower end projecting below thetube and its upper end pervious to a coating medium and disposed in saidhousing to overlie said needle upper ends; a layer of resilient matterabsorbtive of said coating medium and overlying; 7 said material; alayer of elements exerting pressure on: the upper surface of saidresilient matter; and a reservoir of said coating medium Within saidhousing and above;

said layer of resilient matter.

References Cited in the file of this patent UNITED STATES PATENTS

